Asphalt-surfaced roadways have been built to facilitate vehicular travel. Depending upon usage density, base conditions, temperature variation, moisture variation, and/or physical age, the surface of the roadways can eventually become misshapen, non-planar, unable to support wheel loads, or otherwise unsuitable for vehicular traffic. In order to rehabilitate the roadways for continued vehicular use, spent asphalt is removed in preparation for resurfacing.
Cold planers, sometimes also called road mills or scarifiers, are machines that typically include a frame quadrilaterally supported by tracked or wheeled drive units. The frame provides mounting for an engine, an operator's station, and a milling drum. The milling drum, fitted with cutting tools, is rotated through a suitable interface by the engine to break up the surface of the roadway.
In a typical configuration, multiple spiraling rows of cutting tools are oriented on an external surface of the milling drum to converge at a center of the drum. Each row of cutting tools includes a flighting and a plurality of cutting bits connected to the flighting by individual mounting blocks. In some configurations, the flighting is a continuous helical screw. In other configurations, the flighting is formed by individual segments of a helical screw, one segment for each mounting block. The flighting is welded to the external surface of the milling drum at a precise location and in a precise orientation, such that rotation of the milling drum results in desired movement of removed roadway material from the drum onto the center of a tandem conveyor. In addition, each mounting block is welded at a precise location and in a precise orientation onto a corresponding flighting such that the cutting bits are held in optimal positions that productively remove material while providing longevity to the tools. An exemplary milling drum is disclosed in U.S. Pat. No. 7,520,570 of Sansone et al. that issued on Apr. 21, 2009.
Through use of the milling drum, the tool holders can be damaged or broken. If broken at a point inside of the associated tool mounting block, the broken tool holder can be difficult to remove and replace. Unfortunately, this difficulty can result in high repair costs and cause the machine to be unavailable for use for an extended period of time.
The tool holder and milling drum of the present disclosure solve one or more of the problems set forth above and/or other problems in the art.